xref: /linux/drivers/bluetooth/hci_nokia.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Bluetooth HCI UART H4 driver with Nokia Extensions AKA Nokia H4+
4  *
5  *  Copyright (C) 2015 Marcel Holtmann <marcel@holtmann.org>
6  *  Copyright (C) 2015-2017 Sebastian Reichel <sre@kernel.org>
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/errno.h>
11 #include <linux/firmware.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/serdev.h>
19 #include <linux/skbuff.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
22 #include <linux/types.h>
23 #include <linux/unaligned.h>
24 #include <net/bluetooth/bluetooth.h>
25 #include <net/bluetooth/hci_core.h>
26 
27 #include "hci_uart.h"
28 #include "btbcm.h"
29 
30 #define VERSION "0.1"
31 
32 #define NOKIA_ID_BCM2048	0x04
33 #define NOKIA_ID_TI1271		0x31
34 
35 #define FIRMWARE_BCM2048	"nokia/bcmfw.bin"
36 #define FIRMWARE_TI1271		"nokia/ti1273.bin"
37 
38 #define HCI_NOKIA_NEG_PKT	0x06
39 #define HCI_NOKIA_ALIVE_PKT	0x07
40 #define HCI_NOKIA_RADIO_PKT	0x08
41 
42 #define HCI_NOKIA_NEG_HDR_SIZE		1
43 #define HCI_NOKIA_MAX_NEG_SIZE		255
44 #define HCI_NOKIA_ALIVE_HDR_SIZE	1
45 #define HCI_NOKIA_MAX_ALIVE_SIZE	255
46 #define HCI_NOKIA_RADIO_HDR_SIZE	2
47 #define HCI_NOKIA_MAX_RADIO_SIZE	255
48 
49 #define NOKIA_PROTO_PKT		0x44
50 #define NOKIA_PROTO_BYTE	0x4c
51 
52 #define NOKIA_NEG_REQ		0x00
53 #define NOKIA_NEG_ACK		0x20
54 #define NOKIA_NEG_NAK		0x40
55 
56 #define H4_TYPE_SIZE		1
57 
58 #define NOKIA_RECV_ALIVE \
59 	.type = HCI_NOKIA_ALIVE_PKT, \
60 	.hlen = HCI_NOKIA_ALIVE_HDR_SIZE, \
61 	.loff = 0, \
62 	.lsize = 1, \
63 	.maxlen = HCI_NOKIA_MAX_ALIVE_SIZE \
64 
65 #define NOKIA_RECV_NEG \
66 	.type = HCI_NOKIA_NEG_PKT, \
67 	.hlen = HCI_NOKIA_NEG_HDR_SIZE, \
68 	.loff = 0, \
69 	.lsize = 1, \
70 	.maxlen = HCI_NOKIA_MAX_NEG_SIZE \
71 
72 #define NOKIA_RECV_RADIO \
73 	.type = HCI_NOKIA_RADIO_PKT, \
74 	.hlen = HCI_NOKIA_RADIO_HDR_SIZE, \
75 	.loff = 1, \
76 	.lsize = 1, \
77 	.maxlen = HCI_NOKIA_MAX_RADIO_SIZE \
78 
79 struct hci_nokia_neg_hdr {
80 	u8	dlen;
81 } __packed;
82 
83 struct hci_nokia_neg_cmd {
84 	u8	ack;
85 	u16	baud;
86 	u16	unused1;
87 	u8	proto;
88 	u16	sys_clk;
89 	u16	unused2;
90 } __packed;
91 
92 #define NOKIA_ALIVE_REQ   0x55
93 #define NOKIA_ALIVE_RESP  0xcc
94 
95 struct hci_nokia_alive_hdr {
96 	u8	dlen;
97 } __packed;
98 
99 struct hci_nokia_alive_pkt {
100 	u8	mid;
101 	u8	unused;
102 } __packed;
103 
104 struct hci_nokia_neg_evt {
105 	u8	ack;
106 	u16	baud;
107 	u16	unused1;
108 	u8	proto;
109 	u16	sys_clk;
110 	u16	unused2;
111 	u8	man_id;
112 	u8	ver_id;
113 } __packed;
114 
115 #define MAX_BAUD_RATE		3692300
116 #define SETUP_BAUD_RATE		921600
117 #define INIT_BAUD_RATE		120000
118 
119 struct nokia_bt_dev {
120 	struct hci_uart hu;
121 	struct serdev_device *serdev;
122 
123 	struct gpio_desc *reset;
124 	struct gpio_desc *wakeup_host;
125 	struct gpio_desc *wakeup_bt;
126 	unsigned long sysclk_speed;
127 
128 	int wake_irq;
129 	struct sk_buff *rx_skb;
130 	struct sk_buff_head txq;
131 	bdaddr_t bdaddr;
132 
133 	int init_error;
134 	struct completion init_completion;
135 
136 	u8 man_id;
137 	u8 ver_id;
138 
139 	bool initialized;
140 	bool tx_enabled;
141 	bool rx_enabled;
142 };
143 
144 static int nokia_enqueue(struct hci_uart *hu, struct sk_buff *skb);
145 
146 static void nokia_flow_control(struct serdev_device *serdev, bool enable)
147 {
148 	if (enable) {
149 		serdev_device_set_rts(serdev, true);
150 		serdev_device_set_flow_control(serdev, true);
151 	} else {
152 		serdev_device_set_flow_control(serdev, false);
153 		serdev_device_set_rts(serdev, false);
154 	}
155 }
156 
157 static irqreturn_t wakeup_handler(int irq, void *data)
158 {
159 	struct nokia_bt_dev *btdev = data;
160 	struct device *dev = &btdev->serdev->dev;
161 	int wake_state = gpiod_get_value(btdev->wakeup_host);
162 
163 	if (btdev->rx_enabled == wake_state)
164 		return IRQ_HANDLED;
165 
166 	if (wake_state)
167 		pm_runtime_get(dev);
168 	else
169 		pm_runtime_put(dev);
170 
171 	btdev->rx_enabled = wake_state;
172 
173 	return IRQ_HANDLED;
174 }
175 
176 static int nokia_reset(struct hci_uart *hu)
177 {
178 	struct nokia_bt_dev *btdev = hu->priv;
179 	struct device *dev = &btdev->serdev->dev;
180 	int err;
181 
182 	/* reset routine */
183 	gpiod_set_value_cansleep(btdev->reset, 1);
184 	gpiod_set_value_cansleep(btdev->wakeup_bt, 1);
185 
186 	msleep(100);
187 
188 	/* safety check */
189 	err = gpiod_get_value_cansleep(btdev->wakeup_host);
190 	if (err == 1) {
191 		dev_err(dev, "reset: host wakeup not low!");
192 		return -EPROTO;
193 	}
194 
195 	/* flush queue */
196 	serdev_device_write_flush(btdev->serdev);
197 
198 	/* init uart */
199 	nokia_flow_control(btdev->serdev, false);
200 	serdev_device_set_baudrate(btdev->serdev, INIT_BAUD_RATE);
201 
202 	gpiod_set_value_cansleep(btdev->reset, 0);
203 
204 	/* wait for cts */
205 	err = serdev_device_wait_for_cts(btdev->serdev, true, 200);
206 	if (err < 0) {
207 		dev_err(dev, "CTS not received: %d", err);
208 		return err;
209 	}
210 
211 	nokia_flow_control(btdev->serdev, true);
212 
213 	return 0;
214 }
215 
216 static int nokia_send_alive_packet(struct hci_uart *hu)
217 {
218 	struct nokia_bt_dev *btdev = hu->priv;
219 	struct device *dev = &btdev->serdev->dev;
220 	struct hci_nokia_alive_hdr *hdr;
221 	struct hci_nokia_alive_pkt *pkt;
222 	struct sk_buff *skb;
223 	int len;
224 
225 	init_completion(&btdev->init_completion);
226 
227 	len = H4_TYPE_SIZE + sizeof(*hdr) + sizeof(*pkt);
228 	skb = bt_skb_alloc(len, GFP_KERNEL);
229 	if (!skb)
230 		return -ENOMEM;
231 
232 	hci_skb_pkt_type(skb) = HCI_NOKIA_ALIVE_PKT;
233 	memset(skb->data, 0x00, len);
234 
235 	hdr = skb_put(skb, sizeof(*hdr));
236 	hdr->dlen = sizeof(*pkt);
237 	pkt = skb_put(skb, sizeof(*pkt));
238 	pkt->mid = NOKIA_ALIVE_REQ;
239 
240 	nokia_enqueue(hu, skb);
241 	hci_uart_tx_wakeup(hu);
242 
243 	dev_dbg(dev, "Alive sent");
244 
245 	if (!wait_for_completion_interruptible_timeout(&btdev->init_completion,
246 		msecs_to_jiffies(1000))) {
247 		return -ETIMEDOUT;
248 	}
249 
250 	if (btdev->init_error < 0)
251 		return btdev->init_error;
252 
253 	return 0;
254 }
255 
256 static int nokia_send_negotiation(struct hci_uart *hu)
257 {
258 	struct nokia_bt_dev *btdev = hu->priv;
259 	struct device *dev = &btdev->serdev->dev;
260 	struct hci_nokia_neg_cmd *neg_cmd;
261 	struct hci_nokia_neg_hdr *neg_hdr;
262 	struct sk_buff *skb;
263 	int len, err;
264 	u16 baud = DIV_ROUND_CLOSEST(btdev->sysclk_speed * 10, SETUP_BAUD_RATE);
265 	int sysclk = btdev->sysclk_speed / 1000;
266 
267 	len = H4_TYPE_SIZE + sizeof(*neg_hdr) + sizeof(*neg_cmd);
268 	skb = bt_skb_alloc(len, GFP_KERNEL);
269 	if (!skb)
270 		return -ENOMEM;
271 
272 	hci_skb_pkt_type(skb) = HCI_NOKIA_NEG_PKT;
273 
274 	neg_hdr = skb_put(skb, sizeof(*neg_hdr));
275 	neg_hdr->dlen = sizeof(*neg_cmd);
276 
277 	neg_cmd = skb_put(skb, sizeof(*neg_cmd));
278 	neg_cmd->ack = NOKIA_NEG_REQ;
279 	neg_cmd->baud = cpu_to_le16(baud);
280 	neg_cmd->unused1 = 0x0000;
281 	neg_cmd->proto = NOKIA_PROTO_BYTE;
282 	neg_cmd->sys_clk = cpu_to_le16(sysclk);
283 	neg_cmd->unused2 = 0x0000;
284 
285 	btdev->init_error = 0;
286 	init_completion(&btdev->init_completion);
287 
288 	nokia_enqueue(hu, skb);
289 	hci_uart_tx_wakeup(hu);
290 
291 	dev_dbg(dev, "Negotiation sent");
292 
293 	if (!wait_for_completion_interruptible_timeout(&btdev->init_completion,
294 		msecs_to_jiffies(10000))) {
295 		return -ETIMEDOUT;
296 	}
297 
298 	if (btdev->init_error < 0)
299 		return btdev->init_error;
300 
301 	/* Change to previously negotiated speed. Flow Control
302 	 * is disabled until bluetooth adapter is ready to avoid
303 	 * broken bytes being received.
304 	 */
305 	nokia_flow_control(btdev->serdev, false);
306 	serdev_device_set_baudrate(btdev->serdev, SETUP_BAUD_RATE);
307 	err = serdev_device_wait_for_cts(btdev->serdev, true, 200);
308 	if (err < 0) {
309 		dev_err(dev, "CTS not received: %d", err);
310 		return err;
311 	}
312 	nokia_flow_control(btdev->serdev, true);
313 
314 	dev_dbg(dev, "Negotiation successful");
315 
316 	return 0;
317 }
318 
319 static int nokia_setup_fw(struct hci_uart *hu)
320 {
321 	struct nokia_bt_dev *btdev = hu->priv;
322 	struct device *dev = &btdev->serdev->dev;
323 	const char *fwname;
324 	const struct firmware *fw;
325 	const u8 *fw_ptr;
326 	size_t fw_size;
327 	int err;
328 
329 	dev_dbg(dev, "setup firmware");
330 
331 	if (btdev->man_id == NOKIA_ID_BCM2048) {
332 		fwname = FIRMWARE_BCM2048;
333 	} else if (btdev->man_id == NOKIA_ID_TI1271) {
334 		fwname = FIRMWARE_TI1271;
335 	} else {
336 		dev_err(dev, "Unsupported bluetooth device!");
337 		return -ENODEV;
338 	}
339 
340 	err = request_firmware(&fw, fwname, dev);
341 	if (err < 0) {
342 		dev_err(dev, "%s: Failed to load Nokia firmware file (%d)",
343 			hu->hdev->name, err);
344 		return err;
345 	}
346 
347 	fw_ptr = fw->data;
348 	fw_size = fw->size;
349 
350 	while (fw_size >= 4) {
351 		u16 pkt_size = get_unaligned_le16(fw_ptr);
352 		u8 pkt_type = fw_ptr[2];
353 		const struct hci_command_hdr *cmd;
354 		u16 opcode;
355 		struct sk_buff *skb;
356 
357 		switch (pkt_type) {
358 		case HCI_COMMAND_PKT:
359 			cmd = (struct hci_command_hdr *)(fw_ptr + 3);
360 			opcode = le16_to_cpu(cmd->opcode);
361 
362 			skb = __hci_cmd_sync(hu->hdev, opcode, cmd->plen,
363 					     fw_ptr + 3 + HCI_COMMAND_HDR_SIZE,
364 					     HCI_INIT_TIMEOUT);
365 			if (IS_ERR(skb)) {
366 				err = PTR_ERR(skb);
367 				dev_err(dev, "%s: FW command %04x failed (%d)",
368 				       hu->hdev->name, opcode, err);
369 				goto done;
370 			}
371 			kfree_skb(skb);
372 			break;
373 		case HCI_NOKIA_RADIO_PKT:
374 		case HCI_NOKIA_NEG_PKT:
375 		case HCI_NOKIA_ALIVE_PKT:
376 			break;
377 		}
378 
379 		fw_ptr += pkt_size + 2;
380 		fw_size -= pkt_size + 2;
381 	}
382 
383 done:
384 	release_firmware(fw);
385 	return err;
386 }
387 
388 static int nokia_setup(struct hci_uart *hu)
389 {
390 	struct nokia_bt_dev *btdev = hu->priv;
391 	struct device *dev = &btdev->serdev->dev;
392 	int err;
393 
394 	btdev->initialized = false;
395 
396 	nokia_flow_control(btdev->serdev, false);
397 
398 	pm_runtime_get_sync(dev);
399 
400 	if (btdev->tx_enabled) {
401 		gpiod_set_value_cansleep(btdev->wakeup_bt, 0);
402 		pm_runtime_put(&btdev->serdev->dev);
403 		btdev->tx_enabled = false;
404 	}
405 
406 	dev_dbg(dev, "protocol setup");
407 
408 	/* 0. reset connection */
409 	err = nokia_reset(hu);
410 	if (err < 0) {
411 		dev_err(dev, "Reset failed: %d", err);
412 		goto out;
413 	}
414 
415 	/* 1. negotiate speed etc */
416 	err = nokia_send_negotiation(hu);
417 	if (err < 0) {
418 		dev_err(dev, "Negotiation failed: %d", err);
419 		goto out;
420 	}
421 
422 	/* 2. verify correct setup using alive packet */
423 	err = nokia_send_alive_packet(hu);
424 	if (err < 0) {
425 		dev_err(dev, "Alive check failed: %d", err);
426 		goto out;
427 	}
428 
429 	/* 3. send firmware */
430 	err = nokia_setup_fw(hu);
431 	if (err < 0) {
432 		dev_err(dev, "Could not setup FW: %d", err);
433 		goto out;
434 	}
435 
436 	nokia_flow_control(btdev->serdev, false);
437 	serdev_device_set_baudrate(btdev->serdev, MAX_BAUD_RATE);
438 	nokia_flow_control(btdev->serdev, true);
439 
440 	if (btdev->man_id == NOKIA_ID_BCM2048) {
441 		hu->hdev->set_bdaddr = btbcm_set_bdaddr;
442 		set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);
443 		dev_dbg(dev, "bcm2048 has invalid bluetooth address!");
444 	}
445 
446 	dev_dbg(dev, "protocol setup done!");
447 
448 	gpiod_set_value_cansleep(btdev->wakeup_bt, 0);
449 	pm_runtime_put(dev);
450 	btdev->tx_enabled = false;
451 	btdev->initialized = true;
452 
453 	return 0;
454 out:
455 	pm_runtime_put(dev);
456 
457 	return err;
458 }
459 
460 static int nokia_open(struct hci_uart *hu)
461 {
462 	struct device *dev = &hu->serdev->dev;
463 
464 	dev_dbg(dev, "protocol open");
465 
466 	pm_runtime_enable(dev);
467 
468 	return 0;
469 }
470 
471 static int nokia_flush(struct hci_uart *hu)
472 {
473 	struct nokia_bt_dev *btdev = hu->priv;
474 
475 	dev_dbg(&btdev->serdev->dev, "flush device");
476 
477 	skb_queue_purge(&btdev->txq);
478 
479 	return 0;
480 }
481 
482 static int nokia_close(struct hci_uart *hu)
483 {
484 	struct nokia_bt_dev *btdev = hu->priv;
485 	struct device *dev = &btdev->serdev->dev;
486 
487 	dev_dbg(dev, "close device");
488 
489 	btdev->initialized = false;
490 
491 	skb_queue_purge(&btdev->txq);
492 
493 	kfree_skb(btdev->rx_skb);
494 
495 	/* disable module */
496 	gpiod_set_value(btdev->reset, 1);
497 	gpiod_set_value(btdev->wakeup_bt, 0);
498 
499 	pm_runtime_disable(&btdev->serdev->dev);
500 
501 	return 0;
502 }
503 
504 /* Enqueue frame for transmittion (padding, crc, etc) */
505 static int nokia_enqueue(struct hci_uart *hu, struct sk_buff *skb)
506 {
507 	struct nokia_bt_dev *btdev = hu->priv;
508 	int err;
509 
510 	/* Prepend skb with frame type */
511 	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
512 
513 	/* Packets must be word aligned */
514 	if (skb->len % 2) {
515 		err = skb_pad(skb, 1);
516 		if (err)
517 			return err;
518 		skb_put(skb, 1);
519 	}
520 
521 	skb_queue_tail(&btdev->txq, skb);
522 
523 	return 0;
524 }
525 
526 static int nokia_recv_negotiation_packet(struct hci_dev *hdev,
527 					 struct sk_buff *skb)
528 {
529 	struct hci_uart *hu = hci_get_drvdata(hdev);
530 	struct nokia_bt_dev *btdev = hu->priv;
531 	struct device *dev = &btdev->serdev->dev;
532 	struct hci_nokia_neg_hdr *hdr;
533 	struct hci_nokia_neg_evt *evt;
534 	int ret = 0;
535 
536 	hdr = (struct hci_nokia_neg_hdr *)skb->data;
537 	if (hdr->dlen != sizeof(*evt)) {
538 		btdev->init_error = -EIO;
539 		ret = -EIO;
540 		goto finish_neg;
541 	}
542 
543 	evt = skb_pull(skb, sizeof(*hdr));
544 
545 	if (evt->ack != NOKIA_NEG_ACK) {
546 		dev_err(dev, "Negotiation received: wrong reply");
547 		btdev->init_error = -EINVAL;
548 		ret = -EINVAL;
549 		goto finish_neg;
550 	}
551 
552 	btdev->man_id = evt->man_id;
553 	btdev->ver_id = evt->ver_id;
554 
555 	dev_dbg(dev, "Negotiation received: baud=%u:clk=%u:manu=%u:vers=%u",
556 		evt->baud, evt->sys_clk, evt->man_id, evt->ver_id);
557 
558 finish_neg:
559 	complete(&btdev->init_completion);
560 	kfree_skb(skb);
561 	return ret;
562 }
563 
564 static int nokia_recv_alive_packet(struct hci_dev *hdev, struct sk_buff *skb)
565 {
566 	struct hci_uart *hu = hci_get_drvdata(hdev);
567 	struct nokia_bt_dev *btdev = hu->priv;
568 	struct device *dev = &btdev->serdev->dev;
569 	struct hci_nokia_alive_hdr *hdr;
570 	struct hci_nokia_alive_pkt *pkt;
571 	int ret = 0;
572 
573 	hdr = (struct hci_nokia_alive_hdr *)skb->data;
574 	if (hdr->dlen != sizeof(*pkt)) {
575 		dev_err(dev, "Corrupted alive message");
576 		btdev->init_error = -EIO;
577 		ret = -EIO;
578 		goto finish_alive;
579 	}
580 
581 	pkt = skb_pull(skb, sizeof(*hdr));
582 
583 	if (pkt->mid != NOKIA_ALIVE_RESP) {
584 		dev_err(dev, "Alive received: invalid response: 0x%02x!",
585 			pkt->mid);
586 		btdev->init_error = -EINVAL;
587 		ret = -EINVAL;
588 		goto finish_alive;
589 	}
590 
591 	dev_dbg(dev, "Alive received");
592 
593 finish_alive:
594 	complete(&btdev->init_completion);
595 	kfree_skb(skb);
596 	return ret;
597 }
598 
599 static int nokia_recv_radio(struct hci_dev *hdev, struct sk_buff *skb)
600 {
601 	/* Packets received on the dedicated radio channel are
602 	 * HCI events and so feed them back into the core.
603 	 */
604 	hci_skb_pkt_type(skb) = HCI_EVENT_PKT;
605 	return hci_recv_frame(hdev, skb);
606 }
607 
608 /* Recv data */
609 static const struct h4_recv_pkt nokia_recv_pkts[] = {
610 	{ H4_RECV_ACL,		.recv = hci_recv_frame },
611 	{ H4_RECV_SCO,		.recv = hci_recv_frame },
612 	{ H4_RECV_EVENT,	.recv = hci_recv_frame },
613 	{ NOKIA_RECV_ALIVE,	.recv = nokia_recv_alive_packet },
614 	{ NOKIA_RECV_NEG,	.recv = nokia_recv_negotiation_packet },
615 	{ NOKIA_RECV_RADIO,	.recv = nokia_recv_radio },
616 };
617 
618 static int nokia_recv(struct hci_uart *hu, const void *data, int count)
619 {
620 	struct nokia_bt_dev *btdev = hu->priv;
621 	struct device *dev = &btdev->serdev->dev;
622 	int err;
623 
624 	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
625 		return -EUNATCH;
626 
627 	btdev->rx_skb = h4_recv_buf(hu->hdev, btdev->rx_skb, data, count,
628 				  nokia_recv_pkts, ARRAY_SIZE(nokia_recv_pkts));
629 	if (IS_ERR(btdev->rx_skb)) {
630 		err = PTR_ERR(btdev->rx_skb);
631 		dev_err(dev, "Frame reassembly failed (%d)", err);
632 		btdev->rx_skb = NULL;
633 		return err;
634 	}
635 
636 	return count;
637 }
638 
639 static struct sk_buff *nokia_dequeue(struct hci_uart *hu)
640 {
641 	struct nokia_bt_dev *btdev = hu->priv;
642 	struct device *dev = &btdev->serdev->dev;
643 	struct sk_buff *result = skb_dequeue(&btdev->txq);
644 
645 	if (!btdev->initialized)
646 		return result;
647 
648 	if (btdev->tx_enabled == !!result)
649 		return result;
650 
651 	if (result) {
652 		pm_runtime_get_sync(dev);
653 		gpiod_set_value_cansleep(btdev->wakeup_bt, 1);
654 	} else {
655 		serdev_device_wait_until_sent(btdev->serdev, 0);
656 		gpiod_set_value_cansleep(btdev->wakeup_bt, 0);
657 		pm_runtime_put(dev);
658 	}
659 
660 	btdev->tx_enabled = !!result;
661 
662 	return result;
663 }
664 
665 static const struct hci_uart_proto nokia_proto = {
666 	.id		= HCI_UART_NOKIA,
667 	.name		= "Nokia",
668 	.open		= nokia_open,
669 	.close		= nokia_close,
670 	.recv		= nokia_recv,
671 	.enqueue	= nokia_enqueue,
672 	.dequeue	= nokia_dequeue,
673 	.flush		= nokia_flush,
674 	.setup		= nokia_setup,
675 	.manufacturer	= 1,
676 };
677 
678 static int nokia_bluetooth_serdev_probe(struct serdev_device *serdev)
679 {
680 	struct device *dev = &serdev->dev;
681 	struct nokia_bt_dev *btdev;
682 	struct clk *sysclk;
683 	int err = 0;
684 
685 	btdev = devm_kzalloc(dev, sizeof(*btdev), GFP_KERNEL);
686 	if (!btdev)
687 		return -ENOMEM;
688 
689 	btdev->hu.serdev = btdev->serdev = serdev;
690 	serdev_device_set_drvdata(serdev, btdev);
691 
692 	btdev->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
693 	if (IS_ERR(btdev->reset)) {
694 		err = PTR_ERR(btdev->reset);
695 		dev_err(dev, "could not get reset gpio: %d", err);
696 		return err;
697 	}
698 
699 	btdev->wakeup_host = devm_gpiod_get(dev, "host-wakeup", GPIOD_IN);
700 	if (IS_ERR(btdev->wakeup_host)) {
701 		err = PTR_ERR(btdev->wakeup_host);
702 		dev_err(dev, "could not get host wakeup gpio: %d", err);
703 		return err;
704 	}
705 
706 	btdev->wake_irq = gpiod_to_irq(btdev->wakeup_host);
707 
708 	err = devm_request_threaded_irq(dev, btdev->wake_irq, NULL,
709 		wakeup_handler,
710 		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
711 		"wakeup", btdev);
712 	if (err) {
713 		dev_err(dev, "could request wakeup irq: %d", err);
714 		return err;
715 	}
716 
717 	btdev->wakeup_bt = devm_gpiod_get(dev, "bluetooth-wakeup",
718 					   GPIOD_OUT_LOW);
719 	if (IS_ERR(btdev->wakeup_bt)) {
720 		err = PTR_ERR(btdev->wakeup_bt);
721 		dev_err(dev, "could not get BT wakeup gpio: %d", err);
722 		return err;
723 	}
724 
725 	sysclk = devm_clk_get(dev, "sysclk");
726 	if (IS_ERR(sysclk)) {
727 		err = PTR_ERR(sysclk);
728 		dev_err(dev, "could not get sysclk: %d", err);
729 		return err;
730 	}
731 
732 	err = clk_prepare_enable(sysclk);
733 	if (err) {
734 		dev_err(dev, "could not enable sysclk: %d", err);
735 		return err;
736 	}
737 	btdev->sysclk_speed = clk_get_rate(sysclk);
738 	clk_disable_unprepare(sysclk);
739 
740 	skb_queue_head_init(&btdev->txq);
741 
742 	btdev->hu.priv = btdev;
743 	btdev->hu.alignment = 2; /* Nokia H4+ is word aligned */
744 
745 	err = hci_uart_register_device(&btdev->hu, &nokia_proto);
746 	if (err) {
747 		dev_err(dev, "could not register bluetooth uart: %d", err);
748 		return err;
749 	}
750 
751 	return 0;
752 }
753 
754 static void nokia_bluetooth_serdev_remove(struct serdev_device *serdev)
755 {
756 	struct nokia_bt_dev *btdev = serdev_device_get_drvdata(serdev);
757 
758 	hci_uart_unregister_device(&btdev->hu);
759 }
760 
761 static int nokia_bluetooth_runtime_suspend(struct device *dev)
762 {
763 	struct serdev_device *serdev = to_serdev_device(dev);
764 
765 	nokia_flow_control(serdev, false);
766 	return 0;
767 }
768 
769 static int nokia_bluetooth_runtime_resume(struct device *dev)
770 {
771 	struct serdev_device *serdev = to_serdev_device(dev);
772 
773 	nokia_flow_control(serdev, true);
774 	return 0;
775 }
776 
777 static const struct dev_pm_ops nokia_bluetooth_pm_ops = {
778 	SET_RUNTIME_PM_OPS(nokia_bluetooth_runtime_suspend,
779 			   nokia_bluetooth_runtime_resume,
780 			   NULL)
781 };
782 
783 #ifdef CONFIG_OF
784 static const struct of_device_id nokia_bluetooth_of_match[] = {
785 	{ .compatible = "nokia,h4p-bluetooth", },
786 	{},
787 };
788 MODULE_DEVICE_TABLE(of, nokia_bluetooth_of_match);
789 #endif
790 
791 static struct serdev_device_driver nokia_bluetooth_serdev_driver = {
792 	.probe = nokia_bluetooth_serdev_probe,
793 	.remove = nokia_bluetooth_serdev_remove,
794 	.driver = {
795 		.name = "nokia-bluetooth",
796 		.pm = &nokia_bluetooth_pm_ops,
797 		.of_match_table = of_match_ptr(nokia_bluetooth_of_match),
798 	},
799 };
800 
801 module_serdev_device_driver(nokia_bluetooth_serdev_driver);
802 
803 MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
804 MODULE_DESCRIPTION("Bluetooth HCI UART Nokia H4+ driver ver " VERSION);
805 MODULE_VERSION(VERSION);
806 MODULE_LICENSE("GPL");
807